n = 8;
x = rand(n,1);
y = rand(n,1);
plot(x,y,'.')
axis([0 1 0 1])

t = 1:n;
ts = 1:1/10:n;
xs = spline(t,x,ts);
ys = spline(t,y,ts);
hold on
plot(xs,ys,'r');
hold off